Surgical guide for use during sinus elevation surgery utilizing the Caldwell-Luc osteotomy

ABSTRACT

The present invention discloses a surgical guide and accompanying depth bur with a method for its use during sinus elevation surgery utilizing the Caldwell-Luc Osteotomy procedure. The surgical guide of the present invention provides accurate transfer of the parameters of the surgical osteotomy to be performed during sinus elevation surgery. It bridges the gap between the precise information obtained from the CT scan and the surgical field on which this surgical plan must be placed. This is accomplished by the use of the surgical guide which is constructed based on the information in the CT scan and the treatment plan prepared utilizing 3-D imaging software.

FIELD OF THE INVENTION

The present invention relates generally to the field of oralimplantology in the surgical reconstruction of the maxillary sinus inpreparation for dental implant placement. More particularly, the presentinvention relates to a surgical guide and accompanying bur utilized toguide the surgeon in preparation of the osteotomy to enter the maxillarysinus as part of the procedure of sinus elevation and grafting.

BACKGROUND OF THE INVENTION

Following maxillary posterior tooth loss, the maxillary sinuspneumatisizes or expands in every dimension towards the maxilla. As themaxillary bone resorbs, the sinus is enlarged in a coronal, lateral,anterior and posterior direction. This pneumatization, or expansion ofthe maxillary sinus resulting from maxillary bone resorption, leavesless maxillary bone for a platform on which to place dental implants. Ifenough maxillary bone has resorbed, placement of a dental implant wouldpenetrate the floor of the sinus and leave the apical portion of theimplant exposed in the sinus and, thus, not engaged in bone. This wouldresult in no bony support around that portion of the implant and negatethe purpose for dental implant placement as a means of tooth replacementin the posterior maxilla.

In preparation for dental implant placement in the posterior maxilla,the clinician must evaluate the position of the maxillary sinus relativeto the remaining maxillary bone and whether bone resorption has occurredto the point of leaving insufficient amounts of bone for implantplacement. If it is determined that insufficient bone exists forplacement of dental implants due to the expansion of the maxillarysinus, then a sinus elevation and grafting procedure is indicated priorto implant placement.

The prevalent method of sinus elevation and grafting is called theCaldwell-Luc Osteotomy. The procedure involves reflecting a fullthickness mucosal flap to expose the lateral wall of the sinus andmaxilla. A lateral osteotomy is then prepared in the lateral wall of themaxillary sinus. The osteotomy is rectangular in shape and is cut asdeep as the lateral wall of the maxillary sinus until the sinus membrane(Schneiderian membrane) is exposed. The window, or osteotomy, is thencarefully tapped medially to allow entry into the sinus cavity.Afterwards, the sinus membrane is gently elevated from the floor and theanterior and posterior walls of the sinus utilizing various bluntdissecting instruments. After the sinus membrane has been elevated andretracted apically and medially, bone is then placed in the area thatthe sinus membrane has been elevated from. The mucosal flaps are thenapproximated and sutured.

One of the technical difficulties encountered during this procedure isthe inability of the operator to precisely locate the floor of the sinusas he prepares the osteotomy from an antero-posterior direction (alongthe X-Y axis). Since the floor of the sinus can elevate and descendvariably as the osteotomy moves antero-posteriorly, it is impossible tovisualize this course. Therefore, the osteotomy is generally prepared ina straight line higher than the highest point of the sinus floor. Thisguarantees penetration into the sinus floor since an osteotomy that islower than the sinus floor at any point will simply penetrate into themaxillary bone and not into the sinus cavity. This would requireadjustment by expanding the osteotomy superiorly (apically) in order topenetrate the sinus cavity. Obviously, the additional trimming of boneis traumatic and removes bone unnecessarily.

Another error occurs if the osteotomy is placed too superior to thefloor of the sinus. Very careful manipulation must then be effected inorder to negotiate the remaining lateral wall of the sinus inferior tothe osteotomy and to descend below the Schneiderian membrane in order toelevate it from the sinus floor. This technically difficult maneuveringof the instruments along two planes increases the risk of tearing themembrane and thus compromising the outcome of the graft. Otherwise, theosteotomy must be adjusted by expanding in an inferior direction. Thiswould lead to additional trimming of bone and increase the risk oftearing the membrane during the expansion of the osteotomy. It is nearlyimpossible to visualize the variable course of the sinus floor as theosteotomy progresses antero-posteriorly. This inability to visualize thecourse of the sinus floor is the first difficulty encountered in theprocedure.

Another difficulty encountered is the varying thickness of the lateralwall of the sinus as the osteotomy penetrates it to expose theunderlying Schneiderian membrane. The operator must penetrate fullythrough the lateral wall (X-Z axis) in order to raise the window andelevate the membrane. However, if the osteotomy is prepared too deep, itcan tear through the fragile membrane. Therefore, great operator skillis required to visualize the membrane as the osteotomy is preparedthrough a varying depth of the lateral wall and the membrane isapproached.

A further difficulty encountered is the anterior wall of the sinus.Besides the varying depth of the lateral wall, the anterior wall canalso vary in course in the Y-X axis (FIG. 2) just as the floor can varyin course in the X-Y axis (FIG. 2) and the lateral wall can vary inthickness in the Y-Z axis (FIG. 3). Since the osteotomy usually isplaced in a straight line apico-coronally (vertically), whereas theanterior wall is usually not a straight line, portions of the osteotomywould be too far posterior to the anterior wall. This would requiremanipulation anteriorly and then laterally to dissect the membrane fromthe lateral and anterior walls thus increasing the risk of tearing themembrane from the difficult manipulation in two planes. Again, anyadditional adjustments to the osteotomy would cause unnecessary boneremoval and trauma as well as increase the risk of tearing the membrane.

Most of this technique relies on the careful approximation of theoutline of the area of the sinus to be grafted. The osteotomy plannedshould be inside the sinus borders for reasons explained above. Since itis nearly impossible to accurately follow the varying course of thesinus during the osteotomy, inevitably there would be areas that are notexposed by the osteotomy. This would require the careful manipulation ofthe sinus membrane which risks damage to the membrane. Furthermore, asthe lateral wall of the sinus is being cut, the varying thickness of thelateral wall requires that the surgeon proceed very carefully and relyon visual as well as tactile senses to establish that the wall has beenpierced without entering the sinus so as to not damage the immediatelyunderlying membrane.

One of the most reliable methods to graph the maxillary sinus in threedimensions is through a computerized axial tomography (CAT or CT) scanthat renders the sinus in the X, Y and Z planes. The CT scan can then beformatted for evaluation utilizing three-dimensional (3-D) imagingsoftware. The 3-D imaging software allows the clinician to view thesinus in all dimensions as well as to manipulate the image and prepare atreatment plan as to the location and amount of bone to be grafted inthe sinus in order to augment the missing maxillary bone that the sinushas expanded into. This information can then be utilized by the surgeonto establish the parameters of outline and volume of the area of thesinus to be entered for bone grafting.

Even with the information provided by the CT scan utilizing the 3-Dimaging software as to the outline of the sinus in the X, Y and Z planesand all other parameters, there has been no mechanism to accuratelytransfer this highly precise information to the surgical field.Meticulous planning of the parameters of the sinus to be elevated andaugmented has been thwarted by the inaccurate approximation in thetransfer of this information during the surgical procedure.

There has thus been a gap between the extremely precise diagnosticinformation and treatment planning obtained by the CT scan and 3-Dimaging software, and the accurate transfer of that information into thesurgical field to aid the surgeon in executing such a treatment plan.

Accordingly, the objects of the device and method of the presentinvention are to overcome the limitations and drawbacks of the prior artand provide a significant contribution to the state of the art ofreconstructive surgery of the maxillary sinus by providing a surgicalguide and bur and a specific method of use wherein the guide has theadvantages associated with transferring precise data obtained from a CTscan utilizing 3-D imaging software into the surgical field and aidingthe surgeon in such surgery.

SUMMARY OF THE INVENTION

The invention described discloses a surgical guide and accompanyingsurgical bur with a ledge for depth control. The guide is fabricatedfrom acrylic and is based on the treatment plan set forth from thediagnostic information provided by 3-D imaging software from a CT scantaken of a patient. The surgical guide is shaped and dimensioned (i.e.,customized) based on the CT scan and 3-D imaging software results of thesinus area for each patient and accordingly, allows the surgeon toaccurately prepare a Caldwell-Luc osteotomy in all three planes. Theoutline of the osteotomy, as well as the depth of the bone to be removedwithout damaging the underlying the Schneiderian Membrane is createdutilizing the surgical guide and proper depth bur. This permits openaccess to the maxillary sinus cavity within the dimensions required forthe sinus elevation and enables the surgeon easy access to theSchneiderian Membrane without anatomical obstructions.

Previously, this procedure was performed merely with an approximation asto where the floor of the sinus was, where the superior portion was, aswell as where the anterior wall and the posterior wall are located. Inaddition, the variable depth of the lateral wall of the sinus wasaccessed only with the experience and visual sense of the clinicianwithout exact measurements as to the varying thickness of the osteotomyas it moved along the x-y axis. The proposed surgical guide eliminatesall approximations of the osteotomy in the x-y axis as to the outline ofthe osteotomy, as well as along the Z axis as to the depth of theosteotomy so as to prevent any damage of overcutting into theSchneiderian Membrane, and thus enabling easy access into the sinuscavity as outlined by the treatment plan set forth utilizing 3-D imagingsoftware from a CT scan of the patient's maxillary sinus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an image from a CT scan showing three views;

FIG. 2 shows a panoramic view of the maxilla showing the right and leftsinuses (S) along the X-Y axes;

FIG. 2A is the same panoramic view as FIG. 2 showing the design of thearea to be grafted G along the X-Y axis;

FIG. 3 shows cross sectional views of the maxilla and sinus at 1 mmintervals;

FIG. 3A is the same cross section as FIG. 3 showing the design of thearea to be grafted G as well as the Y-Z axis;

FIG. 3B is the same cross section as FIG. 3 with a surgical guide inposition in accordance with the present invention;

FIG. 4 shows a surgical bur having a depth guide in accordance with thepresent invention;

FIG. 5 shows the surgical guide of the present invention in position onthe maxilla with the surgical bur, SB, in place resting on the ledge (L)of the surgical guide in order to penetrate the sinus along the apicalportion of the osteotomy;

FIG. 6 is a panoramic view of the surgical guide G in position showingthe outline of the osteotomy with the coronal C, apical A, anterior ANT,and posterior P aspect of the osteotomy;

FIG. 7 is the same cross sectional view of FIGS. 3B and 5 showing thelateral wall of the sinus after the osteotomy (O) has been prepared; and

FIG. 8 is a top prospective view of the surgical guide illustrating awindow corresponding with the outline of the osteotomy to be preparedwith the apical wall (A), inferior or coronal wall (C), anterior wall(ANT), and posterior wall (P) of the sinus.

To facilitate understanding of the invention, identical referencedesignations have been used, when appropriate, to designate the same orsimilar elements that are common to the figures. Further, unless statedotherwise, the drawings shown and discussed in the figures are not drawnto scale, but are shown for illustrative purposes only.

DETAILED DESCRIPTION OF THE INVENTION

In the oral cavity, when there is tooth loss, the maxillary sinuspneumatisizes, meaning that there is resorption in a three dimensionalplane. The floor of the sinus drops towards the oral cavity, as well asresulting in expansion of the lateral walls. This leaves less maxillarybone for placement of an implant to replace the missing teeth. If theremaining maxillary bone is insufficient to support an implant in termsof height and width, then sinus elevation and bone grafting is requiredin order to regain the resorbed bone. The treatment planning for thesinus elevation involves the patient to receive a CT scan which providesdifferent views of the sinus and maxillary bone (FIG. 1). Thisdiagnostic information allows the surgeon to prepare a treatment planwhich outlines the volume and borders of the area of the sinus to begrafted (FIGS. 2A and 3A).

Referring to FIG. 1, nine sagittal cross-sectional CT scan views alongthe Y-Z axes are illustratively shown for a patient under treatment onthe left side of the drawing. Each of the nine cross-sectional viewsrepresents a slice at a particular millimeter (mm) marking (i.e., 30 mmthrough 38 mm). The CT scan view located on the upper right portion ofFIG. 1 is an axial CT scan through the maxillary antrum, and the CT scanview located on the lower right portion of FIG. 1 is a panoramic viewalong the X-Y axes.

Referring to FIG. 2, an enlarged panoramic view of the CT scan of thelower right portion of FIG. 1 is illustratively shown. The panoramicview is along the X-Y axes, where the right side of the patients face islabeled “R” and the left side of the patients face is labeled “L”. TheX-Y axes are scaled in millimeters. For example, the X-axis includes onemillimeter interval markings starting from twenty (20) mm on the rightside of the patient's upper jaw and continuing left to one hundred andten (110) mm.

The panoramic view of the patient's upper jaw (maxilla) and sinusesillustratively includes a horizontal broken line extending across the CTscan that represents a sinus membrane floor positioning line. The sinusmembrane floor positioning line illustrates that the right sinus(darkened portion labeled “S”) has two sinus portions that extend belowsinus floor membrane and a central portion that extends above sinusfloor membrane. Accordingly, FIG. 2 illustrates that the sinus floor isuneven along the X-axis which may have been caused by resorbsion of thecoronal portion of the maxillary bone.

FIG. 2A is an exploded view of the right sinus area of the panoramicview of FIG. 2. FIG. 2 further illustrates the design of the area to begrafted “G” along the X-Y axis. Reference designation (A) is the apicalportion of the area to be grafted; (C) is the coronal portion; (M) isthe mesial or anterior portion; and (D) is the distal or posteriorportion of the area of the sinus to be grafted.

Referring to FIG. 1, as noted above, the right portion of the drawingillustrates nine (9) cross-sectional views (Z-Y slices) as taken at the30, 31, 32, 33, 34, 35, 36, 37, and 38 mm points along the X-Y axes(FIG. 2). FIG. 3 is an enlarged cross sectional sagittal view of themaxilla and sinus at the 34 mm point (FIG. 1) along the X-axis of thepanoramic view of the maxilla of FIG. 2.

Referring now to FIG. 3, the Z-Y axes are also measured and marked inone millimeter intervals. The arrow (B) indicates the buccal or lateralwall of the sinus, the arrow (F) indicates the floor of the sinus, andthe arrow (M) indicates the maxilla (upper jaw) bone. The darkened arealabeled (S) is the sinus area above the maxilla jaw bone. The sinus area(S) includes areas (darkened portion) that extend below the brokenhorizontal sinus membrane floor positioning line, as well as areas thatextend beyond the desired depth towards the lateral wall of the sinus(S) along the Z-axis, as illustrated by the depth positioning line drawnas the broken line extending vertically along the Y-axis.

FIG. 3A is the same view as FIG. 3 along the Y-Z axes. FIG. 3Aillustrates the portion of the maxilla receiving the bone graph (G).

FIG. 3B is also the same cross sectional view as shown in FIG. 3 andincludes the customized surgical guide (GU and 800 of FIG. 8) of thepresent invention placed in position along the maxilla to enable theosteotomy in accordance with the present invention and prior toperforming the bone graph. The apical (arrow A) and coronal (arrow C)borders of the osteotomy are formed within the guide. As discussed belowin greater detail, the ledge (L) of the guide maintains the standardthickness of 10 mm to penetrate the buccal wall (B) of the sinus (S).

One method which is prevalent for providing sinus elevation and bonegrafting is the Caldwell-Luc Osteotomy. This procedure involvesproviding an opening or window in the lateral wall of the sinus (FIG. 7)and then elevating the sinus membrane (Schneiderian Membrane) in orderto place a bone graft to replace the resorbed bone in the floor andlateral wall of the sinus.

The outline of the osteotomy is dictated by the area that is required tobe grafted. Since it is a three dimensional osteotomy, there is an X, Yand Z component in the plane of the osteotomy. The X and Y componentoutlines the apical, coronal, mesial and distal aspect of the osteotomy(FIG. 6). The Z component outlines the depth of the osteotomy asdictated by the thickness of the lateral wall of the sinus (FIG. 3). Asa surgeon prepares the osteotomy, he approximates the height of thefloor of the sinus as it varies as he travels anteroposteriorly (FIG.2).

Furthermore, the surgeon approximates the mesial (anterior) extent in acoronal-apical direction as well as the distal (posterior) extent in acoronal-apical direction. The surgeon also approximates the occlusaloutline of the osteotomy as it connects the mesial and distal (anteriorand posterior) walls of the osteotomy (FIG. 6). More importantly, thesurgeon must then determine the depth laterally, along the Z axis, ofthe osteotomy within his outline (FIG. 3) so as to penetrate up to theSchneiderian Membrane. This lateral depth varies as the surgeon movesalong the X-Y plane along the outline form. The methodologytraditionally available is the surgeon's view of the color of the boneas it changes as he approaches the piercing of the lateral wall and seesthe grey Schneiderian Membrane.

After the surgeon has cut the outline form of the osteotomy andpenetrated the lateral wall of the sinus (FIG. 7), the surgeon begins toelevate the membrane from the floor of the sinus and graft bone in thesite. Rarely, does the surgeon place his osteotomy exactly on the floorof the sinus (the coronal border) and along the exact anterior border ofthe sinus. Therefore, the surgeon must maneuver the instruments as toseparate the membrane from the sinus floor and anterior and posteriorwalls as there is inevitably a shelf of bone to negotiate.

To assist the surgeon in visualizing the outline of the sinus in threedimensions, a patient can have a CT scan (e.g., DENTASCAN®) performedand formatted by a 3-D imaging computer program (e.g., SIMPLANT®) whichgives different views of the X, Y and Z planes of the sinus (see forexample, FIG. 1). This allows the surgeon to visualize the differentwalls of the sinus and identify their exact depths and outline for theosteotomy. Furthermore, the exact outline in the X-Y axis(antero-posteriorly) can be drawn and planned so the osteotomy isexactly at the floor of the sinus regardless of variations in height asthe osteotomy travels along the X axis (FIG. 6). In addition, theanterior and posterior walls of the osteotomy can be charted so theyfollow along the exact walls of the sinus, thus leaving no shelves forthe sinus elevation instruments to negotiate. The superior wall is alsooutlined as necessary by the height of bone required to be grafted.

Finally, and no less important, as the osteotomy moves along the X-Yplane in preparing the window, the depth of the osteotomy, as dictatedby the thickness of the lateral wall (the Z axis) (see FIG. 3 b), canalso be accurately measured as it varies along the X-Y plane. All thisinformation can be planned as well as visualized by the surgeon, priorto surgery, utilizing the 3-D imaging software. However, to date, therehas been no available mechanism to transfer this information into areliable guide for the surgeon to follow the parameters he/she hasoutlined in the treatment plan.

In one aspect of the present invention, a customized surgical guide (800shown in FIG. 8) is fabricated from acrylic which will replicate theparameters outlined by the surgeon according to the plan proposedutilizing the 3-D imaging software obtained from a CT scan. Theseparameters will assist in preparation of a Caldwell-Luc osteotomy thatis appropriate to the particular, unique and irregular shape of themaxillary bone established by the treatment plan set forth by thesurgeon in the X-Y and Z axes, thereby transferring the information fromthe computer to a guide that can be utilized during the surgicalprocedure. The guide is to be seated on the alveolar ridge afterdissection of the mucosa. The seat is a firm, stable seat without anymovement.

Referring now to FIG. 8, the surgical guide 800 is curvi-linear in shapeand is sized and shaped to correspond to the upper jaw (maxilla) andsinus shape of a particular patient, as determined by the CT scan and3-D imaging software previously administered to the patient. Asillustratively shown in the drawing, the surgical guide 800 includes acurved lower portion 802 having an upper surface 804 adapted forpositioning along the lower edge of the maxilla (alveolar ridge) or theupper teeth (e.g., molars). The curved lower portion extends in anupward direction to form a second portion 806 having an overall height“H” an, overall width “W”, and an overall thickness or depth “D”.

The upward extending second portion 806 includes at least one orifice orwindow 808 illustratively having a somewhat rectangular shape. Theperipheral edges of the window 808 form a ledge 810 that is used inconjunction with a bur (FIG. 4) for performing the osteotomy, asdiscussed below in further detail. The size and shape of the window 808,as well as the depth or thickness of the ledge 810 are formed tocorrespond with the results of the CT scan and 3-D imaging software usedfor planning the osteotomy for a particular patient, such that the lowerportion of the ledge 810 is aligned with and conforms to the shape ofthe bony floor of the sinus cavity and coronal portion of the maxilla.

Referring now to FIG. 4, in another aspect of the present invention, abur 400 with a depth guide 402 is then utilized to prepare the osteotomywithin the outline of the window 808 inside the surgical guide 800. Asshown in the drawing, the bur 400 includes an elongated shaft 404 havinga cutting blade 406 affixed to an end of the shaft 404, as is well knownin the art. The depth guide 402 is affixed transversely across the shaftat a distance of 10 mm from the endpoint (E) of the cutting blade 406,although such distance is not considered limiting.

For example, the surgical bur 400 can have an depth guide 402 whichallows it to maintain a lesser depth, such as 5 mm from the edge of theguide 800 to the point of penetration of the sinus. This alternativesize of the bur guide 402 can be used where the sinus wall is thin and10 mm depth is not necessary in the depth guide 402.

It is well known that the lateral wall of the maxillary bone adjacent tothe maxillary sinus can typically have a thickness in the range ofapproximately 1-5 mm, although other variations in thicknesses are knownto occur. Referring to FIGS. 4 and 5, as the thickness of the lateralwall of the maxillary bone varies, the thickness of the ledge 810 of thewindow 808 of the guide 800 will also vary along the ledge 810 dependingon the thickness of the lateral wall of the maxillary bone to sum to atotal of about 10 mm (guide thickness plus thickness of lateral wall ofmaxillary sinus), since the distance between the endpoint (E) of thedistal end of the cutting blade 406 and the depth guide 402 of the bur400 is at a constant 10 mm. For example, at locations of the maxillathat have a thickness of 2 mm, then the depth of the ledge 810 of thesurgical guide 800 will be 8 mm (10 mm-2 mm). Similarly, where portionsof the maxilla bone is, for example, 5.1 mm thick, then the ledge 810will have a depth of 4.9 mm (10 mm-5.1 mm), and so forth. Accordingly,the thickness of the window ledge varies to conform to the unique shapeand dimensions of the lateral wall of the patient's maxilla bone as itchanges at each position along the X-Y or Y-X axes.

Referring to FIG. 5, the bur 400 is positioned to rest on the ledge 810within the window 808 of the guide 800 so as to maintain a constantcutting depth and not penetrate too far inside the sinus. The ledge 810of the surgical guide 800 is illustratively shown as being thicker atthe bottom (coronal portion) than at the top (apical portion) of theledge 810. Referring to FIG. 7, after the osteotomy has been prepared,the bone within the window 808 of the osteotomy is elevated as the sinusis entered for elevation and grafting. Referring back to FIG. 3A, theportion of the maxilla receiving the bone graph (G) is illustrativelyshown.

Although an exemplary description of the invention has been set forthabove to enable those of ordinary skill in the art to make and use theinvention, that description should not be construed to limit theinvention, and various modifications and variations may be made to thedescription without departing from the scope of the invention, as willbe understood by those with ordinary skill in the art, and the scopethereof is determined by the claims that follow.

1. Surgical guide for performing a sinus elevation procedure on a specific patient's maxillary sinus by penetrating a lateral bony wall proximate a maxillary sinus of the patient, said lateral wall having an external surface, and a varying length, height and depth extending along an X-axis, a Y-axis, and a Z-axis, respectively, said surgical guide comprising: a curvilinear-shaped structure for placement adjacent to and in direct and continuous contact with the external surface of said lateral wall of the maxillary sinus, said curvilinear-shaped structure having a three-dimensional window configured for placement directly over a portion of said lateral wall of the maxillary sinus and to define a surgical site to perform the sinus elevation, said window being sized to receive a dental bur and formed with a patient-specific custom-shaped peripheral edge that defines at least one elongated ledge having a length that extends in a direction along the X-axis of the lateral wall, the ledge having varying surface contours formed in X-Y and Z-X planes extending along the length to correspond to and align with surface contours formed in the X-Y and Z-X planes of the lateral wall at the surgical site, the ledge being configured to provide continuous contact with the lateral wall along its entire length at the surgical site, wherein the ledge includes a variable depth in the Z-X plane and is configured to directly correspond to thickness variations along the Z-X plane of the patient's lateral wall, said window being sized greater than a diameter of the bur to permit movement, guidance and depth control of the bur in three-dimensions along the custom-shaped peripheral edge and surface contours of the window.
 2. The surgical guide of claim 1, wherein said curvilinear-shaped structure includes: a lower portion having a custom-fabricated surface configured for positioning in intimate contact with and over an alveolar ridge of the maxillary bone and/or adjacent teeth of said patient; and an upper portion extending upward from said lower portion for positioning adjacent to and in direct contact with said lateral wall of the maxillary sinus to define said surgical site.
 3. The surgical guide of claim 1, wherein said curvilinear-shaped structure is custom-fabricated from an acrylic material.
 4. The surgical guide of claim 1, wherein said at least one elongated ledge includes at least one of a lower inferior ledge portion having a surface shaped to correspond in shape to an inferior portion of the patient's sinus, an anterior ledge portion having a surface shaped to correspond to an anterior portion of the patient's sinus, a posterior ledge portion having a surface shaped to correspond to a posterior portion of the patient's sinus, or an upper superior ledge portion having a surface shaped to correspond to a superior portion of the patient's sinus, each of said inferior, anterior, posterior and superior ledge portions defining a customized outline guide which corresponds specifically to the surgical site for penetrating the lateral wall of the patient's maxillary sinus.
 5. The surgical guide of claim 1, wherein said custom-shaped peripheral edge defining the window extends from a posterior wall to an anterior wall along the X-Y plane, and the at least one elongated ledge has a customized thickness along the Z-X plane and the Z-Y plane that corresponds to thickness variations along the Z-X plane and the Z-Y plane of the patient's lateral wall.
 6. The surgical guide of claim 1, wherein said custom-shaped peripheral edge defining the window extends from a lower inferior wall to an upper superior wall along the X-Y plane, and the at least one elongated ledge has a customized thickness along the Z-X plane and the Z-Y plane that corresponds to thickness variations along the Z-X plane and the Z-Y plane of the patient's lateral wall.
 7. The surgical guide of claim 1, wherein said at least one elongated edge extending in a direction along the X-axis is concave in shape.
 8. The surgical guide of claim 7, wherein said at least one elongated edge extending in a direction along the X-axis has a surface contour that mimics a surface contour of the lateral wall, wherein the lateral wall of the patient is a convex-shaped lateral wall.
 9. The surgical guide of claim 1, wherein said variable depth in the Z-X plane along the length of the elongated edge provides depth control for penetrating the lateral wall with the bur.
 10. A method of performing sinus elevation surgery to penetrate a bony lateral wall proximate a maxillary sinus of a specific patient, comprising: providing a treatment plan having three-dimensional images which characterize a plurality of bony walls including the lateral wall defining a portion of the maxillary sinus and maxillary bone structures of said patient, said plurality of walls having dimensions, shape, and contours formed along surface portions of the walls that are unique to the patient; and providing a customized surgical guide based on said treatment plan for placement adjacent to and in direct contact with said lateral wall of the patient's maxillary sinus, said guide having a three-dimensional window that defines a surgical site, said window being configured to receive and sized greater than a dental bur which is used to penetrate the lateral wall, said window formed by a customized peripheral edge defining a customized ledge that is elongated in shape, said ledge further including customized surface contours that are positioned to correspond to and align with the uniquely shaped contours formed along external surface portions of the lateral wall, the length of the ledge being configured for continuous contact in its entirety with the lateral wall at the surgical site of the patient, said ledge having a customized thickness to guide and control the depth of penetration of the distal end of the bur while the bur moves in three dimensions along the elongated ledge.
 11. The method of claim 10, further comprising: fixedly placing said customized surgical guide over a portion of an alveolar ridge and/or adjacent teeth, and a portion of a lateral wall of the maxillary sinus of said patient after reflection of a corresponding overlying buccal mucosa; and cutting a portion of said maxillary bone at the surgical site defined by the window by guiding the bur along the customized ledge forming said window.
 12. The method of claim 11, further comprising providing a bone graft in a portion of the maxillary bone and sinus as defined in the treatment plan.
 13. The method of claim 11, wherein said cutting step comprises: providing the bur with a depth guide set a predetermined distance from a distal end of a cutting blade of the bur based on thickness of the maxillary bone structures of said patient acquired during said treatment plan.
 14. The method of claim 11, wherein said placing step further comprises: securing said surgical guide over an alveolar ridge and/or adjacent teeth and lateral wall of the maxillary sinus, such that a lower inferior ledge portion of said window of the surgical guide is aligned at a floor portion of the sinus with a positive seat regardless of variations in height of said floor portion.
 15. The method of claim 10, wherein said providing a surgical guide comprises fabricating the customized surgical guide having said three-dimensional window from an acrylic material.
 16. The method of claim 10, wherein the lateral wall of the patient is convex in shape, said providing the customized surgical guide based on said treatment plan further comprising the step of configuring the elongated ledge with a concave shape to mimic and overlay a portion of the convex-shaped lateral wall, wherein said elongated ledge is configured for continuous contact along its entire length with said adjacent lateral wall at the surgical site.
 17. A surgical guide system for performing a sinus elevation procedure by penetrating an outer surface of an irregularly-shaped lateral wall of a maxillary bone forming a maxillary sinus of a specific patient, the system comprising: a treatment plan including a CT-scan and three-dimensional images which characterize a plurality of walls defining the maxillary sinus and maxillary bone structures of the patient, said plurality of walls having irregular dimensions, shapes, and contours formed along surface portions of the walls that are unique to each patient, said lateral wall having a length extending along an X-axis, a height extending along a Y-axis, and a depth extending along a Z-axis, said lateral wall having a convex-shape extending along the X-axis; a curvilinear-shaped structure having a three-dimensional window for placement directly over a portion of the outer surface of the patient's lateral wall of the maxillary bone to define a surgical site to perform the sinus elevation, said window being sized to receive a dental bur and formed with a customized peripheral edge that defines at least one elongated ledge having a length that extends along the X-axis of the lateral wall, the elongated ledge being concave in shape at least along its inner surface and along the X-axis, and having a surface contour that interfaces with and conforms to a surface contour of the convex-shaped lateral wall of the patient, wherein said elongated ledge is configured for continuous contact along its entire length with the lateral wall at the surgical site; said elongated ledge having a customized variable depth along the Z-axis which corresponds to and aligns with thickness variations of the patient's lateral wall, said window being sized greater than a diameter of the bur to permit movement, guidance and depth control of the bur in three-dimensions along the customized peripheral edge and surface contours of the window; and wherein the curvilinear-shaped structure and window are customized in shape and dimension to conform to the unique and irregularly-shaped and dimensioned lateral wall of the patient's maxillary bone at the surgical site, as determined by the CT-scan and three-dimensional images of the treatment plan.
 18. The surgical guide system of claim 17, wherein said treatment plan comprises at least one of a panoramic, coronal, sagittal and three-dimensional view of the maxillary sinus and maxillary bone structures of said patient.
 19. The surgical guide system of claim 17, wherein the bur is configured to trace and cut the lateral wall at the surgical site while in contact and moving along the ledge of the window.
 20. The surgical guide of claim 19, wherein said bur comprises: an elongated shaft having opposing first and second ends, said first end configured for insertion into a rotary device; a cutting blade coupled to the second end of said shaft; and a depth guide extending transversely from said shaft and spaced a predetermined distance from a distal end of said cutting blade.
 21. The surgical guide of claim 20, wherein said depth guide traverses said shaft a distance in a range of approximately 5-10 mm from the distal end of the cutting blade.
 22. The surgical guide of claim 20, wherein said depth guide is configured to interface with and traverse along said ledge of said window of the curvilinear-shaped structure. 